Wednesday, September 07, 2011

Thought experiment about consciousness

Michael Heap (forensic psychologist and chairman of the Association for Skeptical Enquiry) has sent me the following thought experiment.

You are at the moment taking part in an experiment in which all the activity of your nervous system associated with your conscious experience is being recorded in real time and uploaded onto a computer. This computer is thus having identical conscious experiences as you - perceptions, thoughts, images, memories, feelings, emotions, pain and so on. At some point the scientists announce that the experiment is over and they are about turn off the computer. Do you let them?

6 comments:

(1) I have something of the same reaction as AC; barring details about the recording device I'm reluctant to assume that recording conscious experience and having them is the same. If they are not, then nothing about the scenario seems to make turning off the computer problematic.

(2) But if we get over that by stipulation, my next thought is that the identity of experience between the computer and you means that there is no way to distinguish the computer from you in which it does not turn out that the real experiencer is you. The computer loses nothing by being turned off; the computer's experiences just are your experiences, so as long as you aren't terminated as well, nothing is actually lost by the computer being turned off. The computer, after all, is not experiencing being a computer; its experiences are just your experiences at second-hand. That's an odd situation, your experiences being localizable in two places, but there's still only one real experiencer here, and both you and the computer necessarily agree (so to speak) that it is you.

In a sense it's sort of a hive-mind situation; if the computer is turned off the 'hive mind' -- in this case, your mind -- still goes on, none the worse for the change.

I agree with AC and Brandon's (1). However I don't think I agree with his (2). Experiences are activities, and the activity of my nervous system is not identical with the activity of any computer; even if the formal content is the same there are two distinct acts of two distinct subjects. This leads me to suppose that either a) the experience, if we assume I have only one experience, is not identical either with what is happening in the nervous system or with what is happening in the computer, but with the "universal" formal content, or b) my experience is not that of the computer, despite the similarity or identity of the formal content. If a), then the computer can be shut off with impunity, since the existence of the experience is unaffected; if b) - well, if b) there are further issues to determine. If the computer contains a "copy" of the formal content of the activity of my nervous system and runs it as a program, is this the same as another similar experience? If so, then we're already assuming that consciousness is simply the running of a certain program in a different kind of hardware, which is presumably the question at issue.

In any case, the thought experiment proceeds based on a very questionable assumption, and to my mind its only results will be per impossibile arguments.

I agree with Michael. The mere recording of experience is not the same as experience, any more than the reflection of a person in a mirror is that person.

But if there is experience in the computer (as opposed to recording of experience), these must be separate experiences. And I don't see how the same experience can be localised in different places. If the same form is in two different matters (one the soft machine of the brain, the other the hardware of the computer), are they not actually different things?

I am unconvinced by the idea that experiences are individuated by location; rather, as activities, it seem more plausible to think that they are individuated causally, and all that the recording does is extend the activity of the experience into a medium we are not used to associating with it. An alternative is that experiences are individuated by object. In the scenario the sameness of object goes well beyond what we ordinarily think of as formal content; it's particular, and the experience of a body in the computer is the experience of your body, the experience of a thought in the computer is the experience of your thought, the experience of having an experience is the experience of having your thought. I'm not sure why location would matter.

Suppose, for instance, that we all had, without realizing it, a secondary part of the brain or some other organ that duplicated and stored the memory of your own experience. Surely it would not thereby be regarded as a different experiencer inside you? And, indeed, it would be surprising if none of your experiences do have this sort of redundancy and duplication, even if it's not as systematic or thorough as one organ doing everything. That would be the same experience in two different locations. And if that's the case, then that would suggest to me that what is really at work in the computer case is that the computer is taken to be somehow not one's own -- and that the location is only significant because the experiences are taken to be located both in something that is one's own (brain) and something that is not one's own (computer). But I'd suggest that if the computer is actually recording your very experiences, it has as much reason to be considered one's own as one's brain; it's just happens to be a redundancy.

Suppose we eliminate the redundancy of it: you (1) are capable of reaccessing the stored experiences somehow and (2) undergo some traumatic experience that creates a partial amnesia in you but (3) although the computer continues to record your experiences as a partial amnesiac, it retains all its records in a more accessible way than they are in your own brain because of the difference in medium and location. Then the whole thing would end up being a prosthetic for memory. That would make one hesitate to turn the computer off, but I suspect that people would generally not regard the experiences as separate experiences from one's own.

>>the experience of a body in the computer is the experience of your body

I buy what you said before. But why is it the experience of your body? We know that people with amputated legs still have the experience of their amputated leg. But it's clearly not a physical leg they have experience of. So why can't the computer have an experience of a phantom body (different from your own body) in the way that an amputee experiences a phantom leg?